Background: To evaluate retrospectively long-term results and patterns of recurrence in patients with low-grade non-Hodgkin's lymphoma (NHL) Ann Arbor stage I-II and limited stage III.
Patients and methods: 58 patients, who had been treated between 1980 and 1996, were analyzed. Median follow-up period was 8.75 years. 48 patients (83%) presented with follicular lymphoma (stage I: 23 patients, stage II and III: 15 and ten patients, respectively). Median age was 51 years. Irradiation was applied with a median total dose of 40 Gy. 13 patients (22%) additionally received chemotherapy. End points of the investigation were remission rate, overall- and disease-free survival, and patterns of recurrence, as well as the prognostic impact of age, B-symptoms, chemotherapy, irradiation dose, treatment volume, and Ann Arbor stage.
Results: 6 weeks after treatment 91% of the patients had complete, 7% partial response. One patient (2%) was classified as progressive disease. Overall survival rate was 86% and 69% at 5 and 10 years, respectively. Corresponding disease-free survival rates were 73% and 63%. Regarding overall survival, multivariate analysis identified age (p = 0.001) as independent prognostic factor. In the subgroup of patients with follicular lymphoma 92% were found in complete, 6% in partial remission, one patient (2%) with progressive disease. Overall survival rates at 5 und 10 years were 87% and 70%, disease-free survival rates 75% and 64%, respectively. Out-of-field recurrence rate for all 58 patients was 34% and the proportion of relapses at nodal or lymphatic sites outside the treated areas in relation to all registered recurrences was 77%.
Conclusions: Our results maintain external radiotherapy as a curative concept in the treatment of limited stage low-grade lymphoma, especially in younger patients. Patterns of recurrence would favor total nodal irradiation (TNI) as an appropriate approach for these patients.